A6263: Protected LED Array Driver

The A6263 is a linear, programmable current regulator providing up to 100 mA from each of 4 outputs to drive arrays of high brightness LEDs. Outputs can be connected in parallel or left unused, as required. The regulated LED current from each output, accurate to 5%, is set by a single reference resistor. Current matching in each string is better than 10% without the use of ballast resistors. Driving LEDs with constant current ensures safe operation with maximum possible light output.

The IC provides protection against the following common faults:

LED string shorted to GND

Single or multiple LED short

LED string open

IC pin open/short

Overtemperature

If one LED string is open or shorted to ground, the offending string is disabled, while other LED strings continue to work.

A temperature monitor is included to reduce the LED drive current if the chip temperature exceeds a thermal threshold. If necessary, this thermal derating threshold can be adjusted or disabled.

The device comes in an 8-pin SOIC ( package LJ ) with exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin leadframe plating.

Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro’s product can reasonably be expected to cause bodily harm.